1. Field of the Invention
The present invention concerns an annunciator providing graphic representation of alarm conditions in response to data signals received from a fire detection system or the like. More particularly, the present invention is concerned with an annunciator operable for receiving the data signals as optical signals over a fiber optic cable, and for selectively actuating indicators arranged as a graphic display.
2. Description of the Prior Art
A typical fire protection system includes a plurality of detectors coupled with a central control panel. Upon detection of a fire or other abnormal condition by the detectors, the control panel activates fire extinguishing agents sound alarms, and so forth. Prior art annunciators for use with detection systems include a plurality of lamps or other indicators configured as a graphic representation of the area protected by the detection system and which are activated to illustrate the location of a fire. These prior art annunciators have required a wire connection to each detector in order to activate the corresponding indicator.
As those skilled in the art appreciate, prior art annunciators present a number of problems. For example, the cost of providing a wire connection to each detector can be substantial. Additionally, a short circuit in the connecting wire can cause detector failure. This failure potential has been a barrier to insurance carrier approval of annunciators in fire protection systems.
Known prior art systems have also been limited to one annunciator per system. This can be a disadvantage, for example, in a multi-floor installation where the presence of an annunciator on each floor would help in quickly locating the abnormal condition on that floor.
More recent detection systems use a central control panel which evaluates signals from associated detectors to determine whether an abnormal condition exists and which produces and sends signals representative of these abnormal conditions to an annunciator which processes the data signals and actuates appropriate indicators. These newer installations, however, do not allow multiple annunciators, for example, and tend to be electrically complex and thereby expensive.